The invention relates to a sliding roof for a motor vehicle.
A sliding roof that comprises a shiftable cover arranged for opening and closing a vehicle roof is known from DE 199 02 244 A1. In this arrangement, a sliding headliner which is shiftable underneath the glass cover, is provided with a planar light fixture in order to provide a non-glaring interior space lighting that does not blind the driver. There is the desire to slightly illuminate the interior space during night trips, in order to better see, for example, operating elements, while the illumination must not produce reflections in the window panes and blind the driver. A sliding headliner usually is a very lightweight plate that is made of plastics or compressed fiber materials and can be inserted into an accommodation space; the plate itself and its guide are to be as light as possible and equipped as simply as possible. Due to the arrangement of a lighting device, however, the sliding headliner has to be more rigid and, thus, has a higher weight in order to avoid vibration of the lighting device.
The invention provides a sliding roof with an integrated illumination device that minimizes the tendency of the light source to vibrate and reduces the expenditure for accommodating the light source.
According to the invention, a sliding roof for a motor vehicle comprises a shiftable cover arranged for opening and closing a vehicle roof and at least one electrical light source attached to the cover. The stable, movable cover that closes the outer skin of the vehicle is provided with a very stable guide and for its part is configured stably, so that no enhanced expenditure has to be made for reducing the tendency to vibrate. The lighting for the interior space may be set to such a low level, where appropriate, that it may remain in the ON-state during driving and gives a pleasant feel in the vehicle compartment.
According to one embodiment, the light source is a two-dimensional light source which is attached to the cover, for instance an electroluminescence light source that is often installed in digital clocks for background lighting. In U.S. Pat. No. 4,775,964, which is incorporated herein by reference, and the patent documents mentioned therein there are described such extremely thin, two-dimensional or, in other words, sheet-shaped lighting devices. Single, high-power light sources tend to be blinding or create reflections in the window panes, which is why a sheet-shaped light exit not only provides a more pleasant light, but also for a light which is more suitable for illuminating the interior space.
Further, the light source may be at least one filament bulb, an LED or a gas discharge lamp.
It is further provided for that a lightwave component extends along at least a portion of the edge of the cover and emits light preferably in a direction inwardly of the edge. Due to such arrangement of the lightwave component, the light is emitted in a horizontal plane that is submitted above the occupant and does not or only slightly radiate obliquely downwards, so that the driver will not be blinded by the light. This results in a type of indirect lighting in which spot-like sources are provided, but where the light is radiated through the one or more lightwave component(s).
The lightwave components are, for example, optical waveguides or plexiglass bodies.
According to the invention, the cover has at its inner side a foamed backing or an injection-molded backing provided on the edge of the cover. Preferably, the light source or the lightwave component may be arranged on or in the backing concerned. The foamed backing or the injection-molded backing forms, for instance, a bead-like frame on the inner side of the cover, the lateral surface area of which frame points inwards and comprises a light exit surface area. The light exit surface area may be configured as a surrounding light band or, in other words, a circumferentially extending ring-shaped light exit area, for instance by the light band or the lightwave component being laid on the inner side on the frame and embedded in the foamed or injection-molded backing.
Preferably, the light source is arranged likewise in the foamed or injection-molded backing, which can be done in a very simple manner in that an appropriate accommodation space is left empty during foaming or injection-molding of the backing.
The preferred embodiment of the invention includes a glass plate to form a glass cover.
If appropriate, the glass plate may be coated such or may be roughened on its inner side such that it has an enhanced reflectivity for light from the light source in the direction towards the interior space, as compared with a corresponding plate that is not coated or is not roughened on its inner side. In this embodiment it is considered that the light leaves the light source or the lightwave component at a location very close to the glass plate and at the edge thereof, so that the angle of incidence may be very flat with respect to the inner side of the glass plate and light is hardly reflected in downward directions.